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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug target/114252] Introducing bswapsi reduces code performance Date: Wed, 06 Mar 2024 11:55:14 +0000 [thread overview] Message-ID: <bug-114252-4-CeWUdpFNhk@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-114252-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114252 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Ever confirmed|0 |1 Last reconfirmed| |2024-03-06 Status|UNCONFIRMED |NEW Component|tree-optimization |target Keywords| |missed-optimization --- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> --- Confirmed. It looks like we do no cost evaluation in maybe_optimize_vector_constructor but checking that there's an optab for bswap with SImode. insn-flags.h:#define HAVE_bswapsi2 1 but somehow we end up doing a libcall? We expand as ;; bswapdst_10 = __builtin_bswap32 (load_dst_9); (insn 6 5 7 (set (reg:SI 47) (mem:SI (reg/v/f:HI 46 [ buf ]) [0 MEM <long unsigned int> [(const uint8_t *)buf_5(D)]+0 S4 A8])) -1 (nil)) (insn 7 6 8 (set (reg:SI 22 r22) (reg:SI 47)) -1 (nil)) (insn 8 7 9 (set (reg:SI 22 r22) (bswap:SI (reg:SI 22 r22))) -1 (nil)) ^^^ so why does that turn into a library call? I think this is mis-communication between the middle-end and the target.
next prev parent reply other threads:[~2024-03-06 11:55 UTC|newest] Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top 2024-03-06 10:01 [Bug tree-optimization/114252] New: " gjl at gcc dot gnu.org 2024-03-06 11:55 ` rguenth at gcc dot gnu.org [this message] 2024-03-06 11:59 ` [Bug target/114252] " rguenth at gcc dot gnu.org 2024-03-06 12:15 ` gjl at gcc dot gnu.org 2024-03-06 12:37 ` rguenth at gcc dot gnu.org 2024-03-06 16:12 ` gjl at gcc dot gnu.org 2024-03-06 17:18 ` rguenther at suse dot de 2024-03-07 7:45 ` rguenth at gcc dot gnu.org 2024-03-07 8:45 ` gjl at gcc dot gnu.org 2024-03-07 9:05 ` gjl at gcc dot gnu.org 2024-03-07 9:14 ` rguenth at gcc dot gnu.org 2024-03-07 9:42 ` rguenth at gcc dot gnu.org 2024-03-07 10:47 ` gjl at gcc dot gnu.org 2024-03-07 10:56 ` rguenth at gcc dot gnu.org 2024-03-07 14:12 ` gjl at gcc dot gnu.org 2024-03-07 15:02 ` pinskia at gcc dot gnu.org 2024-03-07 17:52 ` rguenther at suse dot de
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